The following Australian provisional patent applications are hereby incorporated by cross-reference. For the purposes of location and identification, US patent applications identified by their US patent application serial numbers (USSN) are listed alongside the Australian applications from which the US patent applications claim the right of priority.
Not applicable.
This invention relates to a method of tape automated bonding (TAB) alignment in an integrated circuit type device.
When constructing large integrated circuits or micro-electro mechanical systems, it is often necessary to interconnect a large number of wires to the final integrated circuit device or micro-electro mechanical system. Normally, a large number of bond pads are provided on the surface of a chip for the attachment of wires thereto. Bond pads normally require certain minimal spacings in accordance with the design technologies utilized.
Where a large number of interconnects are required, an excessive amount of on chip real estate is required for providing bond pads. It is therefore desirable to minimize the amount of real estate provided for bond pads whilst ensuring the highest degree of accuracy of registration for automated attachment of interconnects such as a tape automated bonding (TAB) to the surface of a device.
In accordance with a first aspect of the present invention, there is provided a method of tape automated bonding alignment in an integrated circuit type device. The integrated circuit type device is of the type having a series of bond pads for the interconnection of the device with external power or communication lines. The method improves the registration accuracy of the interconnection and comprises the step of forming an abutment rail on the device that is spaced adjacent to the bond pads for abutting the external power and communication lines so as to accurately position the lines for interconnection with the bond pads.
Preferably, the bond pads are arranged in a line along one edge of the integrated circuit type device and the lines are in the form of a Tape Automated Bonding strip. The abutment rail can be formed utilizing a standard micromechanical systems deposition process and is ideally utilized in a pagewidth ink jet printing system.
The preferred embodiment of the present invention will be discussed with reference to an example device comprising a page width printhead which is constructed utilizing micro-electro mechanical techniques and requires a large number of interconnects for its proper operation.